To develop specific techniques for in vivo imaging of the mouse with MR microscopy. This will primarily invovle determining animal handling procedures, ventilation, and anesthesia requirements for imaging. This work with the normal mouse is in preparation for future studies using mice for developmental and toxicologic studies. The mouse has been used extensively as a model for many pathologies and in genetic studies. the use of higher resolution MR microscopes such as our 9 T system for in vivo imaging requires that the animal be no bigger than a 20 to 30 g mouse. Currently, we are not able to image this small an animal because of the limitation of our animal support and monitoring systems. This project proposes to solve these problems and make it possible to do non-invasive, survival imaging of mice. This capability of imaging such small animals will make it possible to do many important basic and applied in vivo studies in this important research animal.